According to officials, the monkey was euthanized after contracting the illness, which is caused by the Burkholderia pseudomallei bacterial strain. The animal is the second euthanized in a group of five that were found with antibodies to Burkholderia.

In addition to the fifth monkey being identified, officials said a woman who tested positive for the bacterial strain has been discharged from a hospital. It has not been determined whether she contracted the illness from the Tulane research center or from past travel to an area or country where she was part of an investigative team.

Last month the Louisiana Governor's Office of Homeland Security and Emergency Preparedness and the Louisiana Department of Health and Hospitals held a news conference to announce their findings in a joint investigation that began at the research center late last year after two monkeys fell ill with the bacterial strain.

It was revealed at the time that the woman had contracted the strain shortly after the investigation began. At the time only one of two monkeys had been euthanized, which prompted the U.S. Centers for Disease Control and Prevention and the U.S. Department of Agriculture to join the investigation in Covington.

According to officials, three additional monkeys were identified after exhibiting antibodies to Burkholderia. While two were euthanized, it appears the other three were treated or are still being monitored at the research center.

Currently, researchers are attempting to determine how the strain spread at the facility. While the strain was being studied, the monkeys that fell ill were not purposely exposed to it.

In addition, the research center's veterinary clinic has been decontaminated since the investigation began. While cross-species contamination is possible but very rare, officials believe the strain has been isolated and poses no risk to the public.

"Multiple steps are being taken to caution and advise workers, investigators and neighboring stakeholders while the investigation continues," a spokesperson for St. Tammany Parish government said.

Other members of the investigative team are being tested for possible exposure to the bacteria for baseline comparison and possible future diagnosis. This testing will provide some indication regarding route of transmission.